U.S. patent application number 11/795884 was filed with the patent office on 2008-06-12 for identification medium and article with identification medium.
This patent application is currently assigned to NHK SPRING CO., LTD.. Invention is credited to Hidekazu Hoshino, Hiroyuki Matsumoto, Tokio Sakauchi, Itsuo Takeuchi.
Application Number | 20080136979 11/795884 |
Document ID | / |
Family ID | 36777307 |
Filed Date | 2008-06-12 |
United States Patent
Application |
20080136979 |
Kind Code |
A1 |
Hoshino; Hidekazu ; et
al. |
June 12, 2008 |
Identification Medium and Article with Identification Medium
Abstract
An identification medium 101 has a stacked structure comprising
a fabric 102, an ordinary printed layer 103 of an ordinary black
ink, and an identification layer 104 of an ink including
cholesteric liquid crystals. A predetermined printed character is
formed by the identification layer 104, whereby a print display
utilizing optical characteristics of cholesteric liquid crystals is
formed. The ordinary printed layer 103 functions as a flattening
layer to smooth the asperity of the fabric 102, whereby optical
characteristics of the identification layer 104 is effectively
performed. Thus, the identification medium 101 is comprised of the
fabric 102 as a substrate, whereby the design of articles such as
garments and accessories is not spoiled and discomfort is not
caused.
Inventors: |
Hoshino; Hidekazu;
(Kanagawa, JP) ; Matsumoto; Hiroyuki; (Kanagawa,
JP) ; Sakauchi; Tokio; (Kanagawa, JP) ;
Takeuchi; Itsuo; (Kanagawa, JP) |
Correspondence
Address: |
OLIFF & BERRIDGE, PLC
P.O. BOX 320850
ALEXANDRIA
VA
22320-4850
US
|
Assignee: |
NHK SPRING CO., LTD.
YOKOHAMA-SHI
JP
|
Family ID: |
36777307 |
Appl. No.: |
11/795884 |
Filed: |
February 3, 2006 |
PCT Filed: |
February 3, 2006 |
PCT NO: |
PCT/JP2006/301868 |
371 Date: |
July 24, 2007 |
Current U.S.
Class: |
349/1 |
Current CPC
Class: |
D06P 5/001 20130101;
D06P 1/004 20130101; G09F 3/00 20130101; D06H 1/04 20130101; B41M
3/14 20130101; G09F 3/02 20130101; B42D 25/378 20141001; B42D
25/364 20141001; D06Q 1/00 20130101 |
Class at
Publication: |
349/1 |
International
Class: |
G02F 1/13 20060101
G02F001/13 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 7, 2005 |
JP |
2005-030640 |
Claims
1. An identification medium comprising: a woven or nonwoven fabric;
and an identification layer printed by an ink including cholesteric
liquid crystals on the fabric.
2. The identification medium according to claim 1, wherein an
ordinary printed layer showing a predetermined color is provided
between the identification layer and the fabric.
3. The identification medium according to claim 2, wherein the
ordinary printed layer functions as a light absorption layer.
4. The identification medium according to claim 2, wherein the
ordinary printed layer functions as a flattening layer which
moderates an asperity of the fabric.
5. The identification medium according to claim 1, wherein the
fabric forms a fabric label.
6. The identification medium according to claim 2, wherein the
ordinary printed layer is formed by a thermochromic ink or a
photochromic ink.
7. An article provided with the identification medium according to
claim 1.
Description
TECHNICAL FIELD
[0001] The present invention relates to an identification medium
that allows determination of whether or not articles are authentic
by use of visual effects.
BACKGROUND ART
[0002] Counterfeits of articles (for example, garments, accessories
such as handkerchiefs, shoes, and bags), which are produced by
copying the appearances of authentic articles, are being sold, and
they cause problems. Under these circumstances, in order to ensure
performance, reliability and security of articles and to maintain
the worthiness of the brands of articles, techniques for verifying
the authenticity of the articles are required.
[0003] An identification medium that has a specific appearance may
be used as a method for determining the authenticity of an article.
For example, an identification medium having a function of showing
a hologram, and an identification medium using optical
characteristics of cholesteric liquid crystals are known. For
example, an identifying function using the cholesteric liquid
crystal is disclosed in Japanese Unexamined Patent Application
Publications Nos. 63-51193 and 4-144796.
[0004] The design of the above garments and accessories is very
important. Therefore, it may be undesirable to affix a piece of the
above identification medium thereon. A conventional identification
medium is affixed to an article by using a setting adhesive layer
or an adhesive layer such as a seal. However, the identification
medium having a seal structure is difficult to affix to textiles
such as garments.
DISCLOSURE OF THE INVENTION
[0005] An object of the present invention is to provide an
identification method for determining authenticity in which an
identification medium can be affixed to textiles without spoiling
the design thereof, and there is no discomfort due to articles such
as garments and accessories.
[0006] The present invention provides an identification medium
comprising a woven or nonwoven fabric and an identification layer
that is printed using an ink including cholesteric liquid crystals
on the fabric. According to the present invention, a fabric
provided with an identification portion which shows an optical
characteristic of cholesteric liquid crystals is obtained.
[0007] According to the present invention, the identification
medium is comprised of a fabric as a substrate, whereby the design
of articles such as textiles is not spoiled. Moreover, there is no
discomfort when the identification medium is used with textiles.
Specifically, an identifying ability is provided to a conventional
fabric label by employing the present invention.
[0008] An ink including cholesteric liquid crystals (liquid crystal
ink) is formed by dispersing a cholesteric liquid crystal layer,
which is cut into scale-like pieces, into a vehicle of an ordinary
ink. An ordinary ink is defined as an ink for printing.
[0009] When an ink including cholesteric liquid crystals is printed
in layers, the scale-like cholesteric liquid crystal layer is
distributed in layers and a function of a cholesteric liquid
crystal layer is performed. When an ink including cholesteric
liquid crystals is used, a layer which performs a function of a
cholesteric liquid crystal layer is formed by printing.
[0010] Cholesteric liquid crystals are processed into pigments in
powder form, and are dispersed into an ink solvent, so that an ink
including cholesteric liquid crystals is obtained. Products
produced by Wacker Chemie GmbH are known as pigments in powder form
of cholesteric liquid crystals.
[0011] In the identification medium of the present invention, a
structure is preferably provided with an ordinary printed layer
that shows a predetermined color between an identification layer
and a fabric.
[0012] As mentioned hereinafter, the cholesteric liquid crystal
layer has an optical characteristic in which light having a
predetermined rotation direction and a predetermined wavelength is
reflected, and the rest of the light is transmitted therethrough.
An identifying ability is performed by utilizing this optical
characteristic.
[0013] In the optical function, identification is performed by
viewing reflected light from the cholesteric liquid crystal layer.
Therefore, in order to obtain a good identifying ability, light
transmitted through the cholesteric liquid crystal layer is
required to be partially absorbed by the background (the base side
of the cholesteric liquid crystal).
[0014] The above ordinary printed layer is provided between a
fabric and an identification layer, and the color of the ordinary
printed layer may be appropriately selected, so that the above
requirements are satisfied. For example, as an ink forming the
ordinary printed layer, a black ink or a dark-colored ink is used,
so that the ordinary printed layer functions as a light absorption
layer (a layer which absorbs visible light).
[0015] The above ordinary printed layer functions as a flattening
layer that moderates asperity of a fabric. That is, the surface of
the fabric has asperity of which the size is approximately the
fiber diameter, because the fabric is made of fibers. If an
identification layer is directly printed on a fabric by using an
ink including cholesteric liquid crystals, a stacked structure of
the identification layer is greatly affected by the asperity of the
fabric. That is, the cholesteric liquid crystal layer is spread
along the asperity of the fabric.
[0016] The identification layer comprises a fine structure in which
a scale-like cholesteric liquid crystal layer is distributed in
layers, whereby the scale-like cholesteric liquid crystal layer is
spread in undulating layers if the stacked structure is undulated.
Therefore, each optical axis of scale-like cholesteric liquid
crystal layers (an axis perpendicular to the cholesteric liquid
crystal layer) varies along with the undulating stacked structure.
That is, when the identification layer is viewed from a viewing
angle of 0.degree., each optical axis of the many cholesteric
liquid crystal pieces distributed in the identification layer
varies along with the structure of the undulating form.
[0017] As a result, visual effects of the cholesteric liquid
crystal, which are described below, are decreased. That is, the
optical characteristics of the cholesteric liquid crystal are not
substantial.
[0018] When an ordinary printed layer is provided as a flattening
layer between a fabric and an identification layer, the ordinary
printed layer smoothes the asperity of the fabric. Therefore, the
asperity of the fabric does not greatly affect the identification
layer. Accordingly, although a fabric may be used as a substrate,
the visual effects of the cholesteric liquid crystal are distinct.
That is, when a fabric is applied as a substrate, optical
characteristics of the cholesteric liquid crystal are obtained.
[0019] In the identification medium of the present invention, a
fabric label is preferably made of a fabric. A fabric label is a
small piece of fabric that indicates a brand name, a size,
instructions for washing, etc., on articles such as garments.
Discriminating ability is provided to an article without spoiling
the design thereof by applying the present invention to a fabric
label. That is, an identifying ability obtained by cholesteric
liquid crystals can be provided to a conventional fabric label.
Note that a fabric label on which information is printed is called
a "printed name tag", whereas one on which information is
embroidered is called a "woven name tag".
[0020] In the identification medium of the present invention, a
fabric may be embroidered. According to this aspect, an identifying
ability is provided by a visual effect of cholesteric liquid
crystals combined with a visual effect of embroidery.
[0021] In the identification medium of the present invention, a
printed layer using a thermochromic ink or a photochromic ink may
be used as an ordinary printed layer. When an ordinary printed
layer is comprised of a thermochromic ink or a photochromic ink, a
change in optical characteristics performed by heating and light
irradiation is observed. Accordingly, the identifying ability is
further improved.
[0022] The present invention may be explained as an article
provided with the above identification medium. As articles,
garments, accessories, shoes, bags, stuffed animals, purses, and
other textiles may be mentioned. As accessories, handkerchiefs,
socks, gloves, hats, and neckties may be mentioned.
[0023] A cholesteric liquid crystal is explained as follows. FIG. 3
is a schematic view for showing a structure of cholesteric liquid
crystal layers, and FIG. 4 is a schematic view for explaining
optical characteristics of a cholesteric liquid crystal layer. FIG.
4 shows a condition in which a right-handed circularly polarized
light having a predetermined wavelength is reflected, and a
left-handed circularly polarized light, a linearly polarized light,
and right-handed circularly polarized light having other
wavelengths are transmitted through a cholesteric liquid crystal
layer 201 when natural light enters into the layer.
[0024] The cholesteric liquid crystal layer has a stacked
structure. In one layer, long axes of liquid crystal molecules have
the same orientation and are parallel to the plane thereof in a
layer. The directions of the orientation differ with respect to the
adjacent layer in the direction of layer thickness, and the layers
are stacked with the orientations rotated in a three-dimensional
spiral structure overall.
[0025] In this structure, in a direction perpendicular to the
layer, pitch P is a distance necessary for the molecular long axis
to be rotated through 360.degree. and return to the initial state,
and an average refraction index of the respective layers is index
n. In this case, the cholesteric liquid crystal layer selectively
reflects circularly polarized light having a center wavelength
.lamda.s and a predetermined rotation direction satisfying the
equation .lamda.s=n.times.P. That is, when white light enters into
the cholesteric liquid crystal layer, a right-handed or left-handed
circularly polarized light having a predetermined center wavelength
is selectively reflected. In this case, circularly polarized light
having the same rotation direction as the reflected circularly
polarized light but not having the wavelength of .lamda.s, a
circularly polarized light having a reverse rotation direction to
the reflected circularly polarized light, and a linearly polarized
light are transmitted through the cholesteric liquid crystal
layer.
[0026] The rotation direction (rotating direction) of the reflected
circularly polarized light is determined by selecting a spiral
direction of the cholesteric liquid crystal layer. That is, when
the molecular long axes are viewed from the incident direction of
the light, by selecting either the spiral direction in which the
molecular long axis of each layer orientation is clockwise or is
counterclockwise, the rotation direction (rotating direction) of
the reflected circularly polarized light is determined.
[0027] The cholesteric liquid crystal exhibits an optical
characteristic called "color shifting" in which the color changes
according to the viewing angle. The reason for this is that the
pitch P is apparently decreased when the viewing angle is
increased, and the center wavelength Xs shifts toward shorter
wavelengths. For example, a reflected color of a cholesteric liquid
crystal appears red when the cholesteric liquid crystal is observed
from the perpendicular direction, and it shifts to orange, yellow,
green, blue green, blue in turn according to the increase of the
viewing angle. It should be noted that the viewing angle is defined
as an angle formed by a visual line and a vertical line relative to
the surface of the identification medium.
[0028] According to the present invention, an identification medium
is formed by using cholesteric liquid crystals and a fabric as a
substrate. Therefore, an identification method for determining
authenticity is provided without spoiling the design of textiles,
and there is no discomfort due to articles such as garments and
accessories.
BRIEF DESCRIPTION OF DRAWINGS
[0029] FIG. 1 is a cross section view for showing a cross sectional
structure of an identification medium of the present invention.
[0030] FIG. 2 is a schematic view for showing an identification
medium of the present invention that is observed from the front
side.
[0031] FIG. 3 is a schematic view for showing a stacked structure
of a cholesteric liquid crystal layer.
[0032] FIG. 4 is a schematic view for explaining the optical
characteristics of a cholesteric liquid crystal layer.
EXPLANATION OF REFERENCE NUMERALS
[0033] 101 denotes an identification medium, 102 denotes a fabric,
103 denotes an ordinary printed layer, 104 denotes an
identification layer, and 201 denotes a cholesteric liquid crystal
layer.
BEST MODE FOR CARRYING OUT THE INVENTION
1. First Embodiment
Composition of Embodiment
[0034] FIG. 1 is a cross section view for showing a cross section
structure of an identification medium of the present invention.
FIG. 2 is a front side view of the identification medium shown in
FIG. 1. It should be noted that a cross section taken on line A-A'
of FIG. 2 is the cross section view shown in FIG. 1.
[0035] The identification medium 101 shown in FIG. 1 comprises a
fabric 102, an ordinary printed layer 103, and an identification
layer 104. In this example, the identification medium 101 forms a
fabric label which is sewn on a garment. Moreover, in this example,
as shown in FIG. 2, a printed display "1 2 3" is formed by the
identification layer 104.
[0036] The fabric 102 is a substrate of a fabric label of a woven
fabric made from synthetic fiber. A fabric forming an ordinary
fabric label may be used for the fabric 102.
[0037] An ordinary printed layer 103 is printed on the fabric 102.
The ordinary printed layer 103 is printed with an ordinary black
ink. The ordinary printed layer 103 functions as a flattening layer
that smoothes the asperity of the fabric 102 and forms a flattened
surface.
[0038] That is, the fabric 102 is a woven fabric woven from the
fibers. Therefore, the surface of the fabric 102 has an asperity of
which roughness is a size of approximately the fiber diameter. The
ordinary printed layer 103 smoothes the asperity and provides a
flatter surface.
[0039] An identification layer 104 is formed on the ordinary
printed layer 103. As shown in FIG. 2, the identification layer 104
forms a printed display of the numbers "1 2 3". It should be noted
that the content of the printing may be indicated by characters,
figures, and other appropriate designs in addition to numbers.
[0040] As a liquid crystal ink forming the identification layer
104, a raw material of a liquid crystal ink (a pigment including
cholesteric liquid crystal powder) produced by Wacker Chemie GmbH,
which is dispersed in an ink solvent, may be used as a pigment. In
the present invention, a pigment including cholesteric liquid
crystal layers that selectively reflect right-handed circularly
polarized light in the green is used.
[0041] The identification medium 101 explained in the present
invention may be used for a fabric label, such as one that is
commonly affixed to a garment (for example, shirts and suits). The
fabric label has optical functions of cholesteric liquid
crystals.
[0042] The identification medium 101 can be used in the same way as
a conventional fabric label is used. The identification medium 101
seems to be similar to the conventional fabric label at first
glance. Therefore, an identifying ability for determining
authenticity is provided without spoiling the design of garments.
Moreover, discomfort does not occur when the identification medium
101 is used.
Optical Functions of Embodiment
[0043] Optical functions of the identification medium 101 shown in
FIG. 1 and FIG. 2 are explained. When the identification medium 101
is observed from the front side, a display "1 2 3" of the
identification layer 104 is distinctly visible in green on a black
background. The reason for this is that right-handed circularly
polarized light having a wavelength in the green is selectively
reflected from the identification layer 104, and right-handed
circularly polarized light having other wavelengths, left-handed
circularly polarized light, and linearly polarized light are
transmitted through the identification layer 104 and are absorbed
in the ordinary printed layer 103 in black.
[0044] When the identification medium 101 is observed through an
optical filter which selectively transmits right-handed circularly
polarized light, the identification medium 101 looks the same as
the above identification medium which is directly observed. The
reason for this is that right-handed circularly polarized light in
the green is reflected from the identification layer 104 and is
transmitted through the optical filter, and the light is
observed.
[0045] When the identification medium 101 is observed through an
optical filter that selectively transmits left-handed circularly
polarized right, the green display of the identification layer 104
is dark, and it is difficult to observe. That is, the contrast
(contrast with the black background) of the green display that has
been distinctly observed, is reduced, and an appearance without a
high contrast is observed.
[0046] The reason for this is that the optical filter used in the
above description selectively transmits left-handed circularly
polarized light, and cuts off right-handed circularly polarized
light. That is, right-handed circularly polarized light in the
green is reflected from the identification layer 104 and is cut off
by the optical filter.
[0047] Thus, in the identification medium 101 used as a fabric
label, an identifying ability is obtained by observing through an
optical filter which selectively transmits circularly polarized
light having a predetermined rotation direction. By this
identifying ability, a predetermined printed display is observed or
is difficult to observe. The determination of the authenticity is
performed by using this function. That is, even if a counterfeit
having a similar appearance to that of the identification medium
101 is produced, when an observation is performed through an
optical filter, the counterfeit can be determined to be a
counterfeit as long as the above optical effects are not
confirmed.
[0048] In the present invention, the ordinary printed layer 103 in
black is explained as the simplest example. Furthermore, the
identification layer 104 may be adjusted to have a specific color
by setting the color of the ordinary printed layer 103 (for
example, dark blue or dark red). The setting of the color requires
specialized knowledge because the color relates to the fabric 102,
whereby the identification medium is difficult to reproduce by
appearance alone. Therefore, a counterfeit is difficult to produce.
This is an advantage in an identification medium for determining
authenticity.
[0049] In the present invention, an observation through an optical
filter is exemplified. Moreover, light is irradiated on an
identification medium through an optical filter, and reflected
light may be observed. That is, right-handed or left-handed
circularly polarized light is irradiated on an identification
medium, and the reflected light may be observed.
2. Second Embodiment
[0050] According to the schematic views shown in FIG. 1 and FIG. 2,
patterns or figures may be embroidered on the fabric 102. In this
case, a display of embroidery sewn on the fabric 102 may be
combined with a display of the identification layer 104.
3. Third Embodiment
[0051] A case in which the identification medium 101 shown in FIG.
1 and FIG. 2 is mounted on a necktie as a fabric label is explained
hereinafter. In this case, the identification medium 101 is mounted
on an inside of an end of a necktie as a fabric label.
[0052] The necktie does not seem to differ in appearance from that
of a necktie on which is mounted an ordinary fabric label. However,
when the fabric label is observed through an optical filter which
selectively transmits circularly polarized light having a
predetermined rotation direction, an identifying ability is
performed by specific optical characteristics of cholesteric liquid
crystals. The determination of the authenticity of the necktie is
performed by utilizing this identifying ability. Thus, by utilizing
the present invention, an identifying ability having a superior
level in the determination of authenticity may be given to an
article, without spoiling the conventional design thereof.
[0053] In this example, an identification medium shown in FIG. 2
may be directly formed on the fabric of the necktie. That is, an
ordinary printed layer 103 and an identification layer 104 may be
formed on the fabric that forms the necktie as a substrate, so that
an identifying ability is provided to a portion of the necktie. In
this case, the identifying ability is provided to the necktie
without spoiling the design thereof by utilizing a back fabric of
the necktie.
[0054] In the present invention, the necktie is exemplified as one
of the articles, but a similar composition may be used for other
accessories and garments.
Other Embodiments
[0055] A thermochromic ink (thermosensitive ink) may be used as an
ink for forming an ordinary printed layer 103. For example, an
ordinary printed layer 103 is comprised of a thermochromic ink
which changes from black to a transparent state by heating. In this
case, the above-described optical function is obtained at ordinary
temperature. The ordinary printed layer 103 changes to a
transparent state (or semitransparent state) by heating with an
iron or an appropriate heating method. As a result, a function as a
light absorption layer of the ordinary printed layer 103 is lost
(or reduced), and the above optical function is not obtained. An
identifying ability of the identification medium 101 is further
improved by utilizing this phenomenon.
[0056] As another example of the present invention, a structure may
be mentioned. In the structure, figures such as predetermined
characters, symbols, and patterns are formed on an ordinary printed
layer which is comprised of a thermochromic ink or a photochromic
ink by heating or irradiating a portion of the figures. Moreover,
the overall surface of the ordinary printed layer formed with a
predetermined figure is coated with a liquid crystal ink. In this
structure, the figure formed by heating or irradiating light allows
identification according to a difference of reflection
characteristics. In this structure, the figure formed on the
ordinary printed layer becomes indistinct by heating or irradiating
the overall surface. The determination of the authenticity is
performed by utilizing this phenomenon.
[0057] As a thermochromic ink that becomes transparent by heating,
microencapsulated pigments may be used. The pigment is comprised of
a film containing a photopolymerizable composition and an aliphatic
amine or an aromatic amine, and the film includes reversible heat
allochroic compositions and is ionized by an acid material.
[0058] A thermochromic ink which changes from black (dark color) to
another color, from another color to black (dark color), and from a
transparent state to a predetermined color by heating, may be used,
in addition to a thermochromic ink which changes from black to a
transparent state.
[0059] As an available thermochromic material, a thermochromic ink
(trade name: DynaColor, produced by Chromatic Technologies, Inc.,
United States) may be used.
[0060] An ink (photochromic ink), including a photochromic material
that changes colors and may be in a transparent state by
irradiating light, may be used. In this case, a photochromic layer
changes from black to a light-transparent state by irradiating it
with ultraviolet light, for example.
[0061] A photochromic ink has a property in which a colored state
is changed, not by heat, but by light (for example, ultraviolet
light). A photochromic ink is similar to the thermochromic ink
except that light is used to change the optical characteristics
thereof.
[0062] A photochromic ink is generally made from material that is
photoisomerized by light. As the photochromic ink, azoic dyes,
Schiff chlorine materials, and O-nitrobenzene materials may be
mentioned.
[0063] As an available photochromic ink, a photochromic ink (trade
name: DynaColor, produced by Chromatic Technologies, Inc., United
States) may be used.
INDUSTRIAL APPLICABILITY
[0064] The present invention may be used in identification media
for which the determination of authenticity will be performed by
visual inspection.
* * * * *